The present invention relates to a method of stabilizing caseino-glycomacropeptide (cGMP) in aqueous formulations and reducing an off-flavor formation. In particular, the present invention comprises a formulation, having a pH below about 0.6 and/or, comprising a hydrophobic resin and/or an agent blocking functional groups in the caseino-glycomacropeptide.
Caseino-glycomacropeptide (cGMP) is a glycosylated compound formed during the enzymatic cleavage of kappa-casein from the milk of mammals by the action of rennet or pepsin. To obtain this compound as a starting material, e.g. an acidic casein or a caseinate hydrolyzed by rennet, or even a demineralized, lactose-free sweet whey, is treated with trichloroacetic acid to precipitate the proteins, the supernatant is collected and dialyzed, and finally, the dialysate is dried.
So as to obtain cGMP on an industrial scale acidic casein or sodium or calcium caseinate is treated with rennet which results in the coagulation of para-kappa-casein. The supernatant is then acidified to a pH of about 4–5 in order to precipitate the calcium phospho-caseinate. After separation of the precipitate, the solution is neutralized, demineralized by reverse osmosis, and finally concentrated and dried. Other processes include flocculating whey proteins from whey emanating from cheese production, recovering the supernatant and ultrafiltrating the supernatant using membranes having a cutoff threshold of approximately 15,000 Dalton, thus producing a retentate containing the sialo-glycoproteins.
The cGMP thus obtained is utilized in a variety of different applications, such as in a supplement to nutritional formulas as anti-thrombotic, anti-diarrhoeal compound and for special amino acid diets. Due to its microbizidal activity cGMP is also utilized in formulations for treating bacteria in the buccal cavity which are responsible for the formation of dental plaque and caries. It has been found that the capacity of Actinomyces strains and Streptococcus strains, bacteria populating the buccal cavity and considered to be involved in the initiation and formation of dental plaque, to adhere to buccal epithelial cells, to the surface of teeth coated with saliva and to form co-aggregates with one another may be reduced by providing cGMP in dental formulations, thus diminishing the detrimental effects of said bacterial strains. In addition, cGMP is also described to participate in the effect of a remineralization of demineralized portions of tooth structures.
One of the disadvantages of such formulations, however, resides in that an off-flavor develops during storage thereof. To solve this problem the art has proposed to include binding proteins in the formulations, such as antibodies, as a means of controlling the perceptibility of odoriferous materials which may be present, more specifically undesirable flavors or fragrances or constituents thereof.
Yet, proceeding accordingly is still cumbersome and due to the materials involved also expensive.